Now that rescript-v12.0.0-rc.1 defaults warning to error, I am getting the deprecation warning with the example from the official documentation
How do you model a callback with @this and arity >= 2?
From the doc:
type x
@set external setOnload: (x, @this ((x, int) => unit)) => unit = "onload"
Output:
[W] Line 2, column 35:
deprecated: Js_OO.Callback.arity2
This has been deprecated and will be removed in v13.
FYI, I am porting rescript-mocha to ReScript-v12. It uses many functions that require a callback with @this with various arities.